They might be investors who lent money to the bank by buying its short-term bonds, with a Libor-linked interest rate.

BBC: Libor scandal: Who might have lost?

Underlying the rate worries, bonds -- whose fixed return makes them linked to interest rate and inflation expectations - also weakened.

BBC: Friday close

Guardian Care Homes accuses the bank of mis-selling it an interest rate hedging product linked to the Libor interest rate which Barclays, and other major international banks based in London, are now known to have manipulated.

BBC: Barclays senior staff 'linked' to Libor affair

Until this summer, the London Interbank Rate Offering Rate (LIBOR) was an omnipresent seemingly esoteric instrument that few non-financial people actually paid attention to other than knowing that their interest rate was somehow linked to it.

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One reason why they might do so is that the country has some bonds outstanding where the interest rate to be paid is linked to the officially reported inflation rate.

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Series I bonds consist of two components: a fixed interest rate return and an adjustable inflation-linked return, making them somewhat similar to TIPS. The fixed rate never changes, but the inflation return rate is adjusted every six months and can also be negative (which of course brings your total return down).

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